While this is a fun project, I keep wondering all the time, why we have to do this:
Nissan could give us a nice display of the SOC on the LEAFS built-in dashboard or touchscreen. This really feels like re-inventing the wheel.
Obviously they did not think about it or maybe thought this is information that would confuse the "ordinary" driver. However, at the present stage, most leaf-owners would want something like this (might change when the car goes mass-market), so shouldnt we lobby Nissan to change the software (after all this is all it takes for them...no soldering, CAN-BUS decoding etc. required) instead???? This would be just another option somewhere in the "Energy info" menu. And it would be so much more neat than
any home-built solution!

garygid wrote:I want the voltage and resistance of all the cell-pairs, to evaluate how well they are equalized.

Yes, with the right information, it would probably be a relatively "easy" programming job.

Yes, resistance will especially be important as our modular packs grow in age, and or approach the 100K mile marker. If you haven't driven an EV prior to the Leaf, as traction batterys resistance increases, you'll go from 'full' to 'empty' in much shorter times ... especially pulling a grade / hilly driving.

I saw one of these at the BayLeaf meeting this past Saturday in Redwood City, and it looks pretty slick.

After having seen it, I have a few suggestions (sorry if this is the wrong thread):

- It took me a long long time to find any pictures (online) of what this thing looks like. For the benefit of those who haven't seen one, I would suggest adding a photo to the web site with the order and assembly information, so people can see what they're buying.

- The display can be very difficult to read depending on placement and ambient light. I suspect that adding a red filter (plastic, gel, or whatever they're called) over the display would likely improve help improve readability.

- It's great to see a percentage, which roughly translates to "city miles". It might be nice to also calculate "highway miles" and display both, in a form that shows the "low to high" miles remaining, like "hh:cc", for example: 70:99 or 35:50. I believe this information would be much more useful since it provides a basic "range" of miles remaining, and eliminates the guesswork involved in trying to imagine what the dashboard "guessometer" is currently displaying (city vs. highway, as it tends to fluctuate between the two based on your recent driving).

- I'm also curious whether one of the buttons might (some day, after a firmware update) be used to display tire pressure info. If the LEDs are addressable (rather than just displaying numbers), then you could light up two "corner" segments of one digit, corresponding to the tire location, and then display the tire pressure in the right two digits.